What is the ratio of blood products used in trauma patient resuscitation, specifically the ratio of Red Blood Cells (RBCs) to Fresh Frozen Plasma (FFP) to Platelets?

From the Guidelines

The recommended ratio for blood product resuscitation in trauma patients is 1:1:1 of packed red blood cells (PRBCs), plasma, and platelets, as this balanced approach has been shown to improve outcomes in severely injured patients by addressing the "lethal triad" of hypothermia, acidosis, and coagulopathy that often develops in trauma patients with significant blood loss. This ratio is supported by the most recent and highest quality study, the European guideline on management of major bleeding and coagulopathy following trauma: sixth edition, published in 2023 1. The study suggests that early transfusion with FFP, platelets, and pRBC in fixed ratios may improve survival and haemostasis, and that the 1:1:1 ratio shows improved haemostasis and reduced exsanguination deaths.

The benefits of the 1:1:1 ratio include:

• Improved haemostasis and reduced exsanguination deaths 1
• Reduced mortality rates, particularly in patients with severe bleeding and coagulopathy 1
• Faster achievement of haemostasis, which is critical in trauma patients with significant blood loss 1
• Reduced risk of complications, such as acute respiratory distress syndrome (ARDS), multiorgan failure, and acute kidney injury 1

In contrast, other ratios, such as 1:1:2, may not provide the same level of benefit, and may even increase the risk of complications 1. Therefore, the 1:1:1 ratio is the recommended approach for blood product resuscitation in trauma patients, as it provides the best balance of benefits and risks.

Key points to consider when implementing this strategy include:

• Early initiation of the massive transfusion protocol for patients showing signs of hemorrhagic shock
• Close monitoring of patients' hemostatic capacity and adjustment of the transfusion ratio as needed
• Consideration of the use of coagulation factor concentrates, such as fibrinogen, in patients with significant bleeding and coagulopathy 1

From the Research

Blood Product Ratios in Trauma Resuscitation

The ideal ratio of blood products for resuscitating a trauma patient is a topic of ongoing research and debate.

• A study published in 2015 found that a fresh frozen plasma (FFP) to red blood cells (RBC) ratio of 1:2 had a coagulation effect equivalent to a 1:1 ratio and whole blood 2.
• Another study from 2018 compared resuscitation strategies using combinations of tranexamic acid, prothrombin complex concentrate, and FFP, and found that combinations of FFP with tranexamic acid or prothrombin complex concentrate were superior in improving acidosis, coagulopathy, and clotting time than when these agents were given alone or in combination without plasma 3.
• The use of fibrinogen concentrates, prothrombin complex concentrate, and tranexamic acid in trauma resuscitation has also been explored, with some studies suggesting potential benefits, but more research is needed to fully understand their effects 4, 5, 6.

Key Findings

• FFP:RBC ratio of 1:2 may be equivalent to 1:1 ratio and whole blood in terms of coagulation effect 2.
• Combinations of FFP with tranexamic acid or prothrombin complex concentrate may be superior in improving acidosis, coagulopathy, and clotting time 3.
• Fibrinogen concentrates, prothrombin complex concentrate, and tranexamic acid may have potential benefits in trauma resuscitation, but more research is needed 4, 5, 6.